Diamond composite insert are sintered by carbide matrix and diamond powder at high temperature and high pressure. Adopting a multi-layer structure, the product has extremely high wear resistance while also possessing high impact resistance. Meanwhile, due to the excellent thermal conductivity and wear resistance of diamond, the thermal fatigue failure in the rock breaking process can be greatly reduced during the application. Used on rock breaking tools for oil drilling and mining, it can effectively improve the ability and efficiency of the tool to drill into abrasive formations and extend the service life of the product.